FIELD OF THE INVENTION
[0001] The present invention relates to a system for providing an exacerbation risk score
for a respiratory disease of a patient, and a method for providing an exacerbation
risk score for a respiratory disease of a patient.
BACKGROUND OF THE INVENTION
[0002] The condition of patients with a respiratory disease like asthma can rapidly exacerbate
in the presence of a cold or a flu as well as when prompted by an allergic reaction.
[0003] Asthma exacerbations are potentially fatal and often the exacerbations triggered
by infections are the most serious. Determining the symptoms associated with the onset
of a contagion or an allergy at an early stage is crucial in combating them, and thereby
preventing the deterioration of the patient respiratory function due to exacerbations
of the respiratory disease triggered by the afore-mentioned factors. Early detection
of an allergic reaction and cold or flu symptoms can warn the user and allow them
to take action, specifically to take their regular medicine. Most patients do not
take their medicine all the time but only take it when they perceive a need. An early
warning can indicate the need before the patient is aware of asthma symptoms, and
can contribute to ensure that the patients have their reliever medication with them.
For children, this warning to the parent can help them to manage their child's asthma
effectively. In general, there is no method available in the state of the art that
reliably predicts asthma exacerbations in daily life of a patient. Solutions such
as monitoring exhaled breath or expiratory peak flow are not used in practice due
to the perceived burden on the patient.
For these reasons, it would be advantageous to have a system and a method for providing
an exacerbation risk score for a respiratory disease of a patient that does not suffer
from the above-mentioned drawbacks.
SUMMARY OF THE INVENTION
[0004] It is an object of the present invention to provide a system and a method for providing
an exacerbation risk score for a respiratory disease of a patient, which monitors
unobtrusively the symptoms of an allergic reaction or a contagion like a cold or a
flu.
[0005] The object of the present invention is solved by the subject matter of the independent
claims, wherein further embodiments are incorporated in the dependent claims.
[0006] The described embodiments similarly pertain to the system and the method for providing
an exacerbation risk score for a respiratory disease of a patient. Synergetic effects
may arise from different combinations of the embodiments although they might not be
described in detail.
[0007] Further on, it shall be noted that all embodiments of the present invention concerning
a method, might be carried out with the order of the steps as described, nevertheless
this has not to be the only and essential order of the steps of the method. The herein
presented methods can be carried out with another order of the disclosed steps without
departing from the respective method embodiment, unless explicitly mentioned to the
contrary hereinafter.
[0008] According to a first aspect of the invention, there is provided a system for providing
an exacerbation risk score for a respiratory disease of a patient. The system comprises
a measurement unit configured for measuring a heart signal and/or a blood circulation
signal of a patient and configured for providing corresponding measurement data. The
system comprises a detection unit configured for receiving the measurement data and
for detecting a cough event and/or a sneeze event of the patient in the measurement
data. The system comprises a calculation unit configured for calculating an exacerbation
risk score for a respiratory disease of the patient based on the detected cough event
and/or the detected sneeze event and an interface unit configured for providing the
exacerbation risk score to the patient and/or to a physician.
[0009] The system determines the patient risk of exacerbation of a respiratory disease by
monitoring symptoms such as coughing and sneezing signaling an onset of contagion
and/or an allergy. The symptoms like coughing and sneezing are derived from a measurement
of a heart signal and/or a blood circulation signal. These can be unobtrusively measured
with a measurement unit attached to the body of the patient. The cough event and/or
the sneeze event can be an indicator of an upcoming infection or allergy. A detection
unit is configured for receiving measurement data corresponding to the heart signal
and/or the blood circulation signal form the measurement unit and for detecting a
cough event and/or a sneeze event in the measurement data. A calculation unit calculates
an exacerbation risk score indicating the risk for a deterioration of the respiratory
disease of the patient based on the detected cough and/or sneeze events. The exacerbation
risk score can be used to update an existing value of an exacerbation risk score acquired
in a previous measurement. An interface unit is configured for providing the exacerbation
risk score to the patient. Alternatively or in addition, the exacerbation risk score
can be provided to a care person if the patient, which may be a physician or the parents
in case the patient is a child.
[0010] In an embodiment of the invention, the blood circulation signal comprises at least
on of: blood pressure, blood volume, and blood flow.
[0011] The blood circulation signal comprises a blood pressure, a blood volume, or a blood
flow. In addition, a combination thereof is possible. The heart signal can correspond
to the frequency or the amplitude of the heart beats.
[0012] In an embodiment of the invention, the measurement unit is a wearable unit such as
a bracelet comprising a first sensor for measuring the heart signal and/or the blood
circulation signal.
[0013] The measurement unit can be a wearable device like a bracelet or a wristband comprising
a sensor. It can be worn around the wrist of the patient, or it can be fixed to another
part of the body of the patient. Wristbands measuring vital signs of a patient are
acceptable to the patient and provide an unobtrusive way for measuring the heart signal
and a blood circulation signal of the patient both during daytime and during nighttime.
[0014] In an embodiment of the invention, the first sensor is a photoplethysmographic sensor.
[0015] The sensor of the measurement unit can be a photoplethysmographic sensor. This sensor
can comprise a light source to illuminate a part of the body of the patient, preferably
the skin, and a photodetector, which measures the light reflected from the skin. The
reflected light is influenced by the amount of blood circulating in the skin. Changes
of the amount of blood in the skin can be due to a heartbeat or a change of the blood
pressure, for example.
[0016] In an embodiment of the invention, the respiratory disease is asthma or chronic obstructive
pulmonary disease.
[0017] The respiratory disease of the patient can be asthma or chronic obstructive pulmonary
disease. Further, an exacerbation risk score for any other disease can be provided,
which can deteriorated in the presence of, for example, an allergic reaction or a
contagion like a flu or a cold.
[0018] In an embodiment of the invention, the detection unit is configured for detecting
the cough event by analyzing an inter-beat interval of the heart signal.
[0019] The detection unit can rely on changes in the inter-beat interval of the heart signal
to detect a cough event. The inter-beat interval can be defined as the time elapsing
between two subsequent systolic phases of the heart signal, i.e. the time between
two heartbeats.
[0020] In an embodiment of the invention, the detection unit is configured for detecting
the cough event by a fluctuation of the length of the inter-beat interval over a plurality
of heartbeats.
[0021] The cough detection algorithm of the detection unit can rely on the observation that
during a cough event the heart sinus of the heart signal measured with a photoplethysmographic
sensor can be significantly disrupted. Therefore, the inter-beat interval is significantly
fluctuating as well, and can be used for determining a cough event.
[0022] In addition, the cough detection algorithm can ensure that the detected changes in
the heart sinus are due to a cough event and not to other artefacts such as a relative
movement of the photodetector or the light generating source of the sensor with respect
to the skin. The cough detection algorithm can make use of a patient specific reference
inter-beat interval learned by the detection unit at rest of the patient. This reference
inter-beat interval can be learned by the detection unit at system initialization,
or during run time by adding an accelerometer to the system to identify a patient
resting state while measuring the reference inter-beat interval. A Further, the detection
unit can monitor that a good contact of the sensor to the skin is ensured. A skin-sensor
contact can be maintained and a quality check can be performed and tracked by means
of a quality indicator.
[0023] In an embodiment of the invention, the detection unit is configured for detecting
the sneeze event by analyzing a heart rate of the heart signal and a blood pressure
of the blood circulation signal.
[0024] The detection unit can rely on a change in the heart rate of the heart signal and
a change of the blood pressure of the blood circulation signal to detect a sneeze
event. The heart rate can be defined as the number of heartbeats per time unit. The
blood pressure can also be derived from a blood volume or a blood flow flowing through
the skin of the patient.
[0025] In an embodiment of the invention, the detection unit is configured for detecting
the sneeze event by a decreasing heart rate in temporal correlation with an increasing
blood pressure.
[0026] The algorithm for sneeze detection can rely on the physiologic reaction of the body
of the patient that when the patient sneezes, the intrathoracic pressure in the body
can momentarily increase. This can decrease the blood flow back to the heart. The
heart compensates for this by changing its regular heartbeat momentarily to adjust.
Sneeze events detection can be performed by correlating an abrupt decrease of the
heart rate and a rise in the blood pressure.
[0027] In an embodiment of the invention, the system is configured for storing a record
of exacerbation risk score values of the patient and for providing the record to the
patient and/or to the physician.
[0028] A record of exacerbation risk scores can be stored and a trend of the risk scores
can be provided. Further, the system can provide a signal to the patient, in case
the exacerbation risk score is updated, specifically if the exacerbation risk score
is increased with respect to a precedent measurement of the exacerbation risk score.
[0029] In an embodiment of the invention, the system comprises a second sensor configured
for detecting skin contact, temperature, and/or acceleration.
[0030] This second sensor can be used for verification of the detected signals from the
heart and the blood circuit. The skin contact sensor can detect whether the first
sensor has a good contact to the skin, thereby ensuring that only measurement data
are used for cough and sneeze detection, when the first sensor has good contact to
the skin and provides reliable measurement data. The temperature sensor can be used
to measure the temperature of the skin, and thus a contact of the first and second
sensors to the skin can be monitored. An acceleration sensor can be used to verify
detected cough events and sneeze events, as cough and sneeze events have an influence
to the motion of the body. In addition or as an alternative to an involuntary movement
of the body caused by the cough event or the sneeze event, the patient can use their
hand to cover the mouth, which results in a characteristic acceleration signal of
the acceleration sensor, which can be used to verify the occurrence of a cough or
sneeze event.
[0031] In an embodiment of the invention, the calculation unit comprises an artificial intelligence
module configured for being trained with data from a plurality of patients in order
to predict the exacerbation risk score.
[0032] The exacerbation risk score can be calculated based on a frequency of the detected
cough and sneeze events. The increase or decrease of the score value can be done based
on learning on population data. The data concerning the occurrence of cough and sneeze
events of the patient collected as described above can be combined with other data
that indicate exacerbations and potentially severity of the respiratory disease. For
example, patients with connected reliever inhalers will take their reliever inhaler
one or more times in case of an exacerbation and the number of repetitions and a corresponding
frequency is an indicating of the severity of the exacerbation. Emergency room visits
or hospital admissions and the related physician evaluation can indicate a severity
of the exacerbation. Taking the data from a subset of the population where there is
additional data on exacerbations allows the system as according to the invention to
use machine learning methods to train a model to predict exacerbation risk based on
the detected cough and sneeze events. This machine learning training can ensure that
the patterns that indicate oncoming exacerbations are separated from isolated coughs/sneezes.
After using machine learning on the subset of the population with additional data
concerning the occurrence of cough or sneeze events and a corresponding exacerbation
risk score, the calculation of an exacerbation risk score can be applied to the every
patient of a complete population. The exacerbation risk score can also be personalized
based on the individual situation of the patient. For instance, if one is known to
be allergic to certain pollen, then during corresponding season, the same frequency
of cough/sneeze would be evaluated as a higher exacerbation risk score than during
another season, since the chance of exacerbation of the respiratory disease to be
triggered by pollen can be higher. Another scenario could be that in days with bad
air quality, i.e. unhealthy air quality for a sensitive group of patients, the detection
of frequent cough/sneeze events would also cause more attention on the exacerbation
risk by rating a higher score than on days with good air quality.
[0033] According to another aspect of the invention, there is provided a method for providing
an exacerbation risk score for a respiratory disease of a patient. The method comprises
the steps of measuring a heart signal and/or a blood circulation signal of a patient
and providing corresponding measurement data. The method comprises further the steps
of detecting a cough event and/or a sneeze event of the patient based on the measurement
data and calculating an exacerbation risk score for a respiratory disease of the patient
based on the detected cough event and/or the detected sneeze event. The method comprises
further the step of providing the exacerbation risk score to the patient and/or to
physician.
[0034] The method according to the invention provides an exacerbation risk score for a respiratory
disease of a patient. In a first step, a heart signal and/or a blood circulation signal
of a patient is measured and corresponding measurement data are provided. In the second
step, a cough event and/or a sneeze event of the patient is detected based on the
measurement data. In the third step, an exacerbation risk score for a respiratory
disease of the patient is calculated based on the detected cough event and/or the
detected sneeze event. In the fourth step, the exacerbation risk score is provided
to the patient and/or to a physician.
[0035] According to another aspect of the invention, there is provided a computer program
element, which, when executed on a processing unit, instructs the processing unit
to perform the method according to the preceding aspect of the invention.
[0036] The computer program element can be performed on one or more processing units, which
are instructed to perform the method for providing an exacerbation risk score for
a respiratory disease of a patient when the computer program element is executed.
[0037] According to another aspect of the invention, there is provided a processing unit
configured for executing the computer program element according to the preceding aspect
of the invention.
[0038] The processing unit can be, for example, a processor of a communication device like
a telephone, a smartphone, a tablet, a smart watch, bracelet, or smart glasses. The
processing unit can also be distributed over one or more different devices, such that
a part of the computer program element can be executed on the communication device,
and another part, for example, on a server. The bracelet can be communicationally
connected to the communication device, and an application installed on the communication
device can be configured for performing the steps of the method according to the invention.
[0039] Thus, the benefits provided by any of the above aspects equally apply to all of the
other aspects and vice versa.
[0040] In a gist, the invention relates to a system and a method for providing an exacerbation
risk score for a respiratory disease of a patient. The system measures a heart signal
and/or a blood circulation signal of a patient and detects cough events and sneeze
events in the measurement data. The cough events and sneeze events are indicative
for an onset of a contagion and/or an allergy, which can rapidly exacerbate a respiratory
disease of the patient. Thus, the system is configured for providing unobtrusively
an exacerbation risk score to the patient and/or to a physician.
[0041] The above aspects and embodiments will become apparent from and be elucidated with
reference to the exemplary embodiments described hereinafter. Exemplary embodiments
of the invention will be described in the following with reference to the following
drawings:
BRIEF DESCRIPTION OF THE DRAWINGS
[0042]
Fig. 1 shows a schematic set-up of a system for providing an exacerbation risk score
for a respiratory disease of a patient according to a first embodiment of the invention.
Fig. 2 shows a schematic set-up of a system for providing an exacerbation risk score
for a respiratory disease of a patient according to a second embodiment of the invention.
Fig. 3 shows a schematic set-up of a system for providing an exacerbation risk score
for a respiratory disease of a patient according to a third embodiment of the invention.
Fig. 4 shows the heart signal of a patient measured by the measurement unit during
a cough event of the patient.
Fig. 5 shows a block diagram of a method for providing an exacerbation risk score
for a respiratory disease of a patient according to an embodiment of the invention.
DETAILED DESCRIPTION OF EMBODIMENTS
[0043] Fig. 1 shows a schematic set-up of a system 100 for providing an exacerbation risk
score 170 for a respiratory disease of a patient 150 according to a first embodiment
of the invention. A measurement unit 110 measures a heart signal and/or a blood circulation
signal of a patient 150. Measurement data 160 corresponding to the heart signal and/or
the blood circulation signal are provided and received by the detection unit 120.
The detection unit 120 is configured for detecting a cough event and/or a sneeze event
165 of the patient 150 in the measurement data 160. The calculation unit 130 is configured
for calculating an exacerbation risk score 170 for the respiratory disease of the
patient. This exacerbation risk score 170 is provided by the interface unit 140 to
the patient 150 and/or to a physician.
[0044] Fig. 2 shows a schematic set-up of a system 100 for providing an exacerbation risk
score 170 for a respiratory disease of a patient 150 according to a second embodiment
of the invention. In this embodiment of the invention, the measurement unit 110 is
a wearable device 180 comprising a first sensor 181 and a second sensor 182. The first
sensor 181 is configured for measuring the heart signal and/or the blood circulation
signal of the patient 150. The second sensor 182 is configured for measuring the skin
contact and thus provides data regarding the reliability of the data measured by the
first sensor 181. The measurement data 160 are transmitted to a communication device
300 like a smartphone, a tablet, a smartwatch, smart glasses, etc. However, the wearable
device 180 can be, for example, the smartwatch, or the wearable device 180 can comprise
the detection unit 120, the calculation unit 130 and the interface unit 140. The communication
device comprises in this embodiment of the invention the detection unit 120 for receiving
the measurement data 160 and for detection a cough event and/or a sneeze event 165.
These are provided to the calculation unit 130, which can comprise an artificial intelligence
module 190 trained for providing the exacerbation risk score 170. The exacerbation
risk score 170 is provided by the interface unit 140 to the patient 150 and/or top
a physician. A processing unit 200 can be communicationally connected to the detection
unit 120, the calculation unit 130 and the interface unit 140, and can be configured
for controlling the detection unit 120, the calculation unit 130 and the interface
unit 140 and for executing the steps of the method according to the invention.
[0045] Fig. 3 shows a schematic set-up of a system 100 for providing an exacerbation risk
score 170 for a respiratory disease of a patient 150 according to a third embodiment
of the invention. A wearable unit 180 is attached to the wrist of a patient 150. The
wearable unit 180 can be communicationally connected to a communication device 300,
for example by a wireless connection like WLAN or Bluetooth.
[0046] Fig. 4 shows the heart signal of a patient 150 measured by the measurement unit 110
during a cough event 165 of the patient 150. The amplitude A of a signal measured
by the measurement unit 110 shows usually in case of no cough events and/or sneeze
events a regular, sinus-like waveform measured over time t. In the time interval starting
at t1 and ending at t2, a cough event 165 is detected due to a disruption of the regular
waveform with a significantly fluctuating inter-beat interval.
[0047] Fig. 5 shows a block diagram of a method for providing an exacerbation risk score
170 for a respiratory disease of a patient 150 according to an embodiment of the invention.
The method comprises a first step of measuring a heart signal and/or a blood circulation
signal of a patient and providing corresponding measurement data 160. This step is
followed by a second step of detecting a cough event and/or a sneeze event 165 of
the patient 150 based on the measurement data 160. The third step comprises calculating
an exacerbation risk score 170 for a respiratory disease of the patient 150 based
on the detected cough event and/or the detected sneeze event 165. In the fourth step,
the exacerbation risk score 170 is provided to the patient 150 and/or to a physician.
[0048] While the invention has been illustrated and described in detail in the drawings
and foregoing description, such illustration and description are to be considered
illustrative or exemplary and not restrictive. The invention is not limited to the
disclosed embodiments. Other variations to the disclosed embodiments can be understood
and effected by those skilled in the art in practicing a claimed invention, from a
study of the drawings, the disclosure, and the dependent claims.
[0049] In the claims, the word "comprising" does not exclude other elements or steps, and
the indefinite article "a" or "an" does not exclude a plurality. The mere fact that
certain measures are re-cited in mutually different dependent claims does not indicate
that a combination of these measures cannot be used to advantage. Any reference signs
in the claims should not be construed as limiting the scope.
1. A system (100) for providing an exacerbation risk score for a respiratory disease
of a patient, the system (100) comprising:
a measurement unit (110) configured for measuring a heart signal and/or a blood circulation
signal of a patient (150), and configured for providing corresponding measurement
data (160);
a detection unit (120) configured for receiving the measurement data (160) and for
detecting a cough event and/or a sneeze event (165) of the patient (150) in the measurement
data (160);
a calculation unit (130) configured for calculating an exacerbation risk score (170)
for a respiratory disease of the patient (150) based on the detected cough event and/or
the detected sneeze event (165); and
an interface unit (140) configured for providing the exacerbation risk score (170)
to the patient (150) and/or to a physician.
2. The system (100) according to claim 1,
wherein the blood circulation signal comprises at least on of: blood pressure, blood
volume, and blood flow.
3. The system (100) according to any of the preceding claims,
wherein the measurement unit (110) is a wearable unit (180) such as a bracelet comprising
a first sensor (181) for measuring the heart signal and/or the blood circulation signal.
4. The system (100) according to claim 3,
wherein the first sensor (181) is a photoplethysmographic sensor.
5. The system (100) according to any of the preceding claims,
wherein the respiratory disease is asthma or chronic obstructive pulmonary disease.
6. The system (100) according to any of the preceding claims,
wherein the detection unit (120) is configured for detecting the cough event (165)
by analyzing an inter-beat interval of the heart signal.
7. The system (100) according to claim 6, wherein the detection unit (120) is configured
for detecting the cough event (165) by a fluctuation of the length of the inter-beat
interval over a plurality of heartbeats.
8. The system (100) according to any of the preceding claims,
wherein the detection unit (120) is configured for detecting the sneeze event (165)
by analyzing a heart rate of the heart signal and a blood pressure of the blood circulation
signal.
9. The system (100) according to claim 8, wherein the detection unit (120) is configured
for detecting the sneeze event (165) by a decreasing heart rate in temporal correlation
with an increasing blood pressure.
10. The system (100) according to any of the preceding claims,
wherein the system (100) is configured for storing a record of exacerbation risk score
values of the patient (150) and for providing the record to the patient (150) and/or
to the physician.
11. The system (100) according to any of the preceding claims,
wherein the system (100) comprises a second sensor (182) configured for detecting
skin contact, temperature, and/or acceleration.
12. The system (100) according to any of the preceding claims,
wherein the calculation unit (130) comprises an artificial intelligence module (190)
configured for being trained with data from a plurality of patients in order to predict
the exacerbation risk score (170).
13. A method for providing an exacerbation risk score (170) for a respiratory disease
of a patient (150), the method comprising the steps of:
measuring a heart signal and/or a blood circulation signal of a patient and providing
corresponding measurement data (160);
detecting a cough event and/or a sneeze event (165) of the patient (150) based on
the measurement data (160);
calculating an exacerbation risk score (170) for a respiratory disease of the patient
(150) based on the detected cough event and/or the detected sneeze event (165); and
providing the exacerbation risk score (170) to the patient (150) and/or to a physician.
14. A computer program element, which, when executed on a processing unit (200), instructs
the processing unit (200) to perform the method according to claim 13.
15. A processing unit (200) configured for executing the computer program element according
to claim 14.